Esne-gazuratik eratorritako film biodegradagarriak

Cheese factories in Euskadi produce a significant amount of whey and its discharge can cause important environmental damages. Therefore, the objective of this study was to prepare biodegradable films using whey protein. In this way, the films prepared with proteins obtained from agroindustrial bio-waste not only will reduce the amount of food waste, but also may help increase the shelf life of foodstuffs. Among different film manufacturing techniques, compression moulding was selected to produce films based on whey protein with the aim of reducing production time and promoting more sustainable processes. After optimising the film manufacturing process, the physical, chemical, barrier, optical and mechanical properties of the films were assessed. In addition to the properties of the films, an environmental impact study of the samples was conducted as well.; Euskadiko gaztandegietan esne-gazur ugari sortzen da eta haren isurketak kalteak eragin ditzake ingurumenean. Horregatik, ikerketa honen helburua film biodegradagarriak ekoiztea da, esne-gazuraren proteina erabiliz. Elikagaien industriako bio-hondakinetatik datorren proteinan oinarritutako elikadura-ontzien bidezko irtenbide honek, hondakinen kopurua murrizteaz gain, elikagaien bizitza erabilgarria handitzea du helburu. Esne-gazuraren proteinan oinarritutako filmak sortzeko, hainbat prozesatze-metodo erabil daitezke eta, lan honetan, konpresioa aukeratu da, ekoizpen-denborak murrizteko eta prozesu iraunkorragoak sustatzeko. Filmen eraketa-prozesua optimizatu ondoren, lortutako filmen propietate fisiko-kimikoak, optikoak, mekanikoak eta hesi-propietateak aztertu dira. Horretaz gain, filmen ingurumen-inpaktuaren azterketa egin da

Composite films based on chitosan and epigallocatechin gallate grafted chitosan: Characterization, antioxidant and antimicrobial activities

The effect of chitosan-epigallocatechin gallate conjugate (CS-EGCG) at various ratios (10:0, 9:1, 8:2, 7:3, 6:4 and 5:5, w/w) and glycerol (30 and 50%, w/w) on mechanical, barrier and optical properties of CS films and CS/CS-EGCG composite films was studied. CS films added with 30 or 50% glycerol (CS-30G or CS-50G, respectively) had high tensile strength and elongation at break. Generally, CS/CS-EGCG composite films had higher resistance to light transmission than CS films (p < 0.05). With augmenting concentrations of CS-EGCG, films with lower lightness (L*) and higher redness (a*) and yellowness (b*) were obtained. Therefore, among composite films, those with CS/CS-EGCG ratio of 8:2, containing 30 or 50% glycerol, were selected for further analyses in comparison to CS films. Composite films, regardless of glycerol levels, showed higher antioxidant and antimicrobial activities as compared to CS films (p < 0.05). Overall, CS/CS-EGCG (8:2) composite films had satisfactory physical properties with increased antimicrobial and antioxidant activities and could serve as promising packaging for food shelf-life extension

From seafood waste to active seafood packaging: An emerging opportunity of the circular economy

Sustainable development is an overarching objective that requires an interdisciplinary approach in order to address the societal challenge concerning climate action, environment, resource efficiency and raw materials. In this context, valorization of abundant and available bio-wastes with high potential to manufacture value-added products is the first step to close the loop between waste and consumption in line with the main goal of the circular economy. In the last years, many research works have been published in the literature regarding novel food packaging. However, most of them are focused on packaging composition (scientific aspects) and some of them on the packaging manufacture (technological aspects), but very few studies are concerned about the influence of bringing novel food packaging systems into the market on environmental, social and economic issues. In this regard, this review intends to fill this gap, considering the potential of developing food packaging from food processing waste in order to create business for food industries, being aware of the food quality demanded by consumers and the environmental care demanded by institutions and society

Sustainable Sheep Wool/Soy Protein Biocomposites for Sound Absorption

The wool fibers of the Latxa sheep breed were combined with a soy protein isolate (SPI) matrix to develop sustainable biocomposites with acoustic properties, adding value to Latxa sheep wool, which is currently considered a residue. Samples with 7, 10, 15, and 20 wt % wool were prepared by freeze drying in order to develop porous structures, as shown by SEM analysis. Additionally, XRD analysis provided the evidence of a change toward a more amorphous structure with the incorporation of wool fibers due to the interactions between the soy protein and keratin present in wool fibers, as shown by the relative intensity changes in the FTIR bands. The biocomposites were analyzed in a Kundt’s tube to obtain their sound absorption coefficient at normal incidence. The results showed an acoustic absorption coefficient that well-surpassed 0.9 for frequencies above 1000 Hz. This performance is comparable to that of the conventional synthetic materials present in the market and, thus, sheep wool/SPI biocomposites are suitable to be used as acoustic absorbers in the building industry, highlighting the potential of replacing not only synthetic fibers but also synthetic polymers, with natural materials to enhance the sustainability of the building sector

THE EFFECT OF PLASTICIZER CONTENT AND DISACCHARIDE TYPE ON THE MECHANICAL, BARRIER AND PHYSICAL PROPERTIES OF BOVINE GELATIN-BASED FILMS

Gelatins are regarded as alternative raw materials to prepare films for food packaging. However, the improvement of their mechanical and water barrier properties is necessary in order to obtain useful materials in service conditions. To improve these functional properties, two strategies have been carried out in this work. First, glycerol was added as plasticizer to increase the flexibility of the films. Second, lactose or sucrose was added to react with gelatin and increase water resistance of gelatin-based films. Commercial gelatin, glycerol and lactose or sucrose were employed in this work and processing of the films was carried out by solution casting. All gelatin films obtained were transparent and flexible. Moreover, the hydrophobic character of the films was increased and the film solubility was decreased by the addition of glycerol and disaccharides. As was observed via FTIR, the changes were due to the interactions between gelatin and glycerol and Maillard reaction between gelatin and disaccharides

Whey Protein Films for Sustainable Food Packaging: Effect of Incorporated Ascorbic Acid and Environmental Assessment

The management of food waste and by-products has become a challenge for the agri-food sector and an example are whey by-products produced in dairy industries. Seeking other whey valorisation alternatives and applications, whey protein films for food packaging applications were developed in this study. Films containing different amounts (0, 5, 10, and 15 wt%) of ascorbic acid were manufactured via compression-moulding and their physicochemical, thermal, barrier, optical, and mechanical properties were analysed and related to the film structure. Additionally, the environmental assessment of the films was carried out to analyse the impact of film manufacture. Regarding physicochemical properties, both FTIR and water uptake analyses showed the presence of non-covalent interactions, such as hydrogen bonding, between whey protein and ascorbic acid as band shifts at the 1500–1700 cm−1 region as well as a water absorption decrease from 380% down to 240% were observed. The addition of ascorbic acid notably improved the UV-Vis light absorbance capacity of whey protein films up to 500 nm, a relevant enhancement for protecting foods susceptible to UV-Vis light-induced lipid oxidation. In relation to the environmental assessment, it was concluded that scaling up film manufacture could lead to a reduction in the environmental impacts, mainly electricity consumption

Properties and application of bilayer films based on poly (lactic acid) and fish gelatin containing epigallocatechin gallate fabricated by thermo-compression molding

An alternative approach towards production of active bilayer films based on poly (lactic acid) (PLA) and fish gelatin incorporated with epigallocatechin gallate (EGCG) fabricated by thermo-compression molding was investigated. This strategy permitted the reduction of production times and avoided the uses of inorganic solvents. Thermo-compression molded bilayer films showed good handling, transparency and low water vapor permeability. The incorporation of EGCG promoted interactions with gelatin, as shown by Fourier transform infrared spectroscopy. These interactions contributed to homogeneous structures, as observed by scanning electron microscopy. Bilayer films with 12 wt % EGCG showed good mechanical properties, high water and UV–visible light barrier properties as well as a high DPPH radical scavenging activity. These bilayer films were used to produce bags, in which striped catfish slices (SCS) were packaged. After 7 days of storage at 4 °C, SCS packaged in bags prepared with12 wt % EGCG had lower psychrophilic bacteria count, weight loss, peroxide value, and thiobarbituric acid reactive substances (TBARS) value along with higher docosahexaenoic acid (C22:6 n-3) content than those packaged in bags prepared without EGCG or in LLDPE bags. No difference in overall likeness score was found among all the samples packaged in different bags after 7 days of storage. Therefore, PLA/gelatin bilayer films containing 12 wt % EGCG possessed satisfactory film properties with augmented antioxidant activity, and thus they could be used as active food packaging, especially for fish slices with high lipid content

Influence of phenoxy addition on the curing kinetics for uncatalyzed and catalized cyanate ester resin

The curing behavior of the dicyanate ester of bisphenol-A (DCBA) modified with poly(hydroxy ether of bisphenol-A) (phenoxy) is studied by differential scanning calorimetry in dynamic and isothermal tests at temperatures between 120 and 240°C. The addition of phenoxy to DCBA produces an increase in the reaction rate and a decrease in the temperature of maximum reaction rate for the uncatalyzed resin, and also for the system catalyzed with copper (II) acetyl acetonate/nonylphenol. The exothermic heat of curing for the mixtures is also dependent on the phenoxy content. These facts evidence a catalytic effect of phenoxy on the curing of the cyanate ester resin, even though an autocatalytic behavior is observed for all uncatalyzed DCBA/phenoxy mixtures. A simplified mechanistic kinetic model is used to calculate the kinetic parameters. For the uncatalyzed systems, a decrease in the kinetic constant for the initiation reactions, and an increase in the propagation constant are measured when the cyanate content increases. The thermal activation energy for the initiation reaction of the catalyzed systems is lower than that of the uncatalyzed ones, and it depends on the weight fraction of cyanate in the mixture.Fil: Remiro, Pedro M.. Universidad del Pais Vasco; EspañaFil: de la Caba, Koro. Universidad del Pais Vasco; EspañaFil: Mondragon, Iñaki. Universidad del Pais Vasco; EspañaFil: Riccardi, Carmen Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigación en Ciencia y Tecnología de Materiales (i); Argentina. Universidad Nacional de Mar del Plata. Facultad de Ingeniería; Argentin